Creating geometry based on the transparency of a PNG image
You can start from plane

from bottom extruding (E) on Y axis, scale (S) and repeat process up to top.
add Subsurface Modifier
Sharp edge (Shift+E) = 1 (pink edges)



Unwrap (U) &gt; Project from View
switch to UV Edit layout (from top row) and adjust position on image in edit mode



(if you need more smooth shape increase Modifier)

You can start from Curve Object

add Curve &gt; Bezier
(in edit mode select and delete all, click with Ctrl to create a new point)
Extrude (E) selected point to shape
change handle type (V) for corner points



From half of shape you can generate 3D object by Screw Modifier

Convert to Mesh object you can use Boolean Modifier to Intersect another object to finish cut.



You can use Knife tool

go to edit mode hit (K) Knife to do cuts arround the drawing, but it is a bit dirty way, since plane is already Unwrapped moving points will move texture as well (there was an option to disable moving UV, but I cant find it now). To smooth shape in specific part you can use Subdivision Surface modifier as well, but triangulate it first.


Example all of them (Plane visible, others are hidden from Outliner)


You can use Greace Pencil

to redraw icon from scratch